Standards in Stem Cell Research

The ambition in many quarters to scale up the production of human embryonic stem cells and move towards clinical trials requires that different laboratories are able to produce to a standard quality of cells.

Standards in stem cell research help both scientists and regulators to manage uncertainty and the unknown, according to new research funded by the Economic and Social Research Council. Efforts to standardize practices across different labs are, however, a balancing act where the autonomy of scientists and fragility of living material need to be weighed against the need for comparable data.

The ambition in many quarters to scale up the production of human embryonic stem cells and move towards clinical trials requires that different laboratories are able to produce to a standard quality of cells. Developing common standards in stem cell production is not straightforward as so much is still unknown in this new science.

Professor Andrew Webster and Dr. Lena Eriksson of York University interviewed and observed a range of scientists and technicians working in stem cell laboratories in the UK, USA, and Sweden.

Accurately describing human embryonic stem cell lines is one way to begin setting standards. A stem cell line is a family of constantly-dividing cells, the product of a single parent group of stem cells. Embryonic stem cells are unique in that they have yet to 'decide' which developmental path to choose: They have the ability to turn into almost all human cell types. However, each human embryonic stem cell holds the genetic signature of the donor which differs between donors just as people themselves differ. Further the state of a stem cell is by its very nature temporary as it is defined by its ability to develop into many different cell types.

Some scientists argued that as the stem cell cannot be standardized, the process and materials used should be standardized. Currently, differences in laboratory practices are thought to result in differences in stem cell lines reflecting the way they are treated rather than an innate quality of the lines themselves. The skills of the laboratory technician also play a key role. But pinpointing all the factors that contribute to producing successful stem cell lines remains elusive. "Scientists often explain that their laboratory produces successful human embryonic stem cell lines because their laboratory uses the factor X when they grow them or its lab technicians have green fingers," says Dr. Lena Eriksson of the research team.

Some researchers prefer not to develop standards as these will constrain the science and may close off promising areas of research. "Others argue that it is simply futile," explains Lena Eriksson. "Can you standardize how all children sleep by giving them the same bed, sheet, and blanket? Of course not. So why bother standardizing the materials of stem cell production when other differences such as donor history and derivation methods are so complex, manifold and, to date, largely unknown?"

However, the research shows most stem cell scientists are keen to collaborate on the technical side as they feel this is necessary in order to move the field as a whole forward. The research team followed one particularly successful effort - the International Stem Cell Initiative - that adopted a multi-sited experimental approach in which a large number of stem cell lines were analyzed and compared.

Because of the imprecise nature of the manual laboratory work, standardization opens a potential market for automation technologies to be introduced into human embryonic stem cell laboratories. Yet the research shows this also brings tensions. By attracting businesses keen to become suppliers of laboratory material for this emerging market, the expense of such equipment as well as the skills and staff needed to operate it may exclude small laboratories. Even those that can afford to meet the costs have reservations about the robustness of stem cells to withstand the automation process. The relationship between standards, automation, and stem cell quality will be key to the future scale-up of the field and so its clinical application.